The present invention relates generally to film wrapping or packaging machines, and more particularly to a new and improved film clamping assembly which facilitates the wrapping or packaging of loads within wrapping or packaging film in a more secure manner, particularly short loads having relatively small height dimensions, which facilitates the wrapping or packaging of loads within the wrapping or packaging film in less time and with less wrapping or packaging film required for the overall film wrapping or packaging cycle or operation, which facilitates the wrapping or packaging of loads within the wrapping or packaging film without encountering or developing any interference between the film clamping assembly and the wrapping or packaging film, and which facilitates the wrapping or packaging of loads within the wrapping or packaging film by reducing the risk of tearing of the film during the packaging or wrapping operation or cycle.
Film wrapping or packaging machines are of course well-known in the industry and are exemplified by means of U.S. Pat. No. 5,862,647 which issued to Scherer et al. on Jan. 26, 1999, U.S. Pat. No. 5,477,658 which issued to Berger et al. on Dec. 26, 1995, U.S. Pat. No. 5,447,008 which issued to Martin-Cocher on Sep. 5, 1995, U.S. Pat. No. 5,414,979 which issued to Moore et al. on May 16, 1995, U.S. Pat. No. 4,914,891 which issued to Suolahti on Apr. 10, 1990, U.S. Pat. No. 4,497,159 which issued to Lancaster, III on Feb. 5, 1985, and U.S. Pat. No. 4,302,920 which issued to Lancaster et al. on Dec. 1, 1981. Film packaging or wrapping machines often comprise two different types of machines, that is, a first type wherein the load to be wrapped is disposed upon a turntable which rotates the load relative to a supply roll of wrapping or packaging film which is mounted upon a vertically reciprocably movable carriage mechanism, or a second type wherein the load is stationary, and the vertically reciprocably movable carriage mechanism, having the supply roll of wrapping or packaging film mounted thereon, is mounted upon an arm or boom which rotates around the load. In either type of machine or system, a film clamping mechanism is provided for initially clamping or grasping a leading end portion of the wrapping or packaging film so as to properly position or orient the leading end portion of the wrapping or packaging film in connection with the subsequent initiation and application of the wrapping or packaging film upon the load in accordance with the performance of a wrapping or packaging operation or cycle. Conventionally, such film clamping mechanisms comprise a pair of upstanding clamping members which are relatively movable with respect to each other between CLOSED and OPENED positions so as to clamp or grasp the wrapping or packaging film, or to unclamp or release the wrapping or packaging film, respectively. As a result of the upstanding disposition of the clamping members, as well as in view of their positional location within the vicinity of the load being wrapped or packaged, such conventional clamping members pose an operational or cyclic interference problem with the film dispensing mechanism which must be accommodated by means of the manner in which the wrapping or packaging operation or cycle is conducted.
For example, in view of the upstanding disposition of the clamping members, the vertically movable carriage member, upon which the supply roll of wrapping or packaging film is mounted, must initially be disposed at an elevational level above that of the upstanding clamping members such that the wrapping or packaging film does not encompass or envelop the clamping members thereby preventing their subsequent movement to their OPENED positions when release of the wrapping or packaging film is desired. In addition, when a load to be wrapped comprises a short load having a relatively small height dimension, and in view of the fact that the wrapping or packaging film is conventionally twenty inches (20.00xe2x80x3) wide, and in view of the additional fact that the wrapping or packaging of the load must be commenced at an elevational level above that of the clamping members which can have a vertical extent of, for example, between eight and ten inches (8.00-10.00xe2x80x3), the wrapping or packaging film may only in effect be partially disposed upon the load whereby the wrapping or packaging film is not in fact securely disposed in its wrapped state upon the load.
Still further, when the wrapping or packaging operation or cycle is being completed, the carriage assembly, upon which the supply roll of wrapping or packaging film is disposed, cannot be continuously lowered to its lowermost travel position in order to enable the lowermost region of the load to be wrapped or packaged because, again, interference with the upstanding clamping members will occur. Accordingly, in order to compensate for, or accommodate, such potential interference so as to in fact avoid such operational interference, it is conventional for the downward movement of the carriage mechanism to be terminated at an elevational level which is above that of the upper extent of the clamping members so as to permit the clamping members to then be moved to their OPENED positions thereby enabling further lowering of the carriage assembly. However, opening of the clamping fingers obviously results in the release of the leading end or tail of the wrapping or packaging film which must then be immediately captured and secured by means of the packaging or wrapping film being wrapped around the load in order to prevent any subsequent difficulties in connection with the wrapping, packaging, or further processing of the load. However, depending upon the relative circumferential locations of the clamping mechanism and the carriage assembly from which the packaging or wrapping film is dispensed, which is a function of the size of the load and the wrapping or packaging of the same within the wrapping or packaging film, the turntable or rotating arm may have to be rotated a predetermined amount so as to circumferentially locate or position the clamping mechanism and the carriage assembly at a predetermined position with respect to each other just prior to the opening of the clamping members and the release of the leading end or tail of the wrapping or packaging film so as to effectively ensure the capture and securing of the leading end or tail of the wrapping or packaging film by means of the subsequently wrapped packaging or wrapping film.
Once this is accomplished, dispensing of the wrapping or packaging film in a horizontal reinforcing wrap mode is continued for several relative rotations of the load and the film dispensing assembly whereupon completion of the securing of the leading end or tail portion of the wrapping or packaging film, lowering of the carriage assembly is continued to its lowermost extent so as to complete the film wrapping or packaging operation. When the carriage assembly attains its lowermost position, further reinforcing or bottom wrapping of the load, as is well-known in the industry, is performed upon the lowermost portion of the load so as to complete the entire wrapping or packaging operation or cycle. Subsequently, the packaging or wrapping film can again be relatively disposed above the clamping members such that the clamping members can be moved to their CLOSED positions so as to once again clamp the wrapping or packaging film. A suitable film welding and cutting mechanism is then activated so as to secure a trailing end portion of the wrapping or packaging film to the load and to sever such trailing end portion of the wrapping or packaging film from the leading end portion of the wrapping or packaging film which is now clamped by means of the clamping members in preparation for a new film wrapping or packaging operation or cycle to be performed upon a new load. It can therefore be readily appreciated that in accordance with the PRIOR ART clamping assembly or mechanism, a dual or double horizontal reinforcing wrapping of the load within the vicinity of the clamping fingers and upon the bottom portion of the load has been necessary. This cyclic operation is wasteful both in connection with operational processing time as well as with respect to the use of additional wrapping or packaging film.
A need therefore exists in the art for a new and improved film clamping assembly, and a method of operating the same, for use in connection with film wrapping or packaging machines wherein in addition to the clamping members being movable with respect to each other between their OPENED and CLOSED states, the clamping members can be pivotally moved between a first vertically oriented RAISED position, during which time, for example, the clamping members can capture a portion of the wrapping or packaging film in preparation for the commencement of a wrapping or packaging operation or cycle, and a second horizontally oriented LOWERED position, during which time, for example, the clamping members can retain the captured portion of the packaging or wrapping film while the film wrapping or packaging operation or cycle is being performed, such that the clamping members do not present any interference with respect to the wrapping or packaging film being wrapped around the load, as a result of which, not only can the wrapping or packaging film be applied to the lowermost regions of the load, but in addition, cyclic operation time is shortened and less packaging or wrapping film is required to be used in connection with the wrapping or packaging of a particular load.
Accordingly, it is an object of the present invention to provide a new and improved film clamping assembly, and a method of operating the same, for use in connection with film wrapping or packaging machines.
Another object of the present invention is to provide a new and improved film clamping assembly, and a method of operating the same, for use in connection with film wrapping or packaging machines, wherein the new and improved film clamping assembly effectively overcomes the various operational drawbacks or disadvantages characteristic of conventional PRIOR ART film clamping assemblies.
An additional object of the present invention is to provide a new and improved film clamping assembly, and a method of operating the same, for use in connection with film wrapping or packaging machines, wherein the new and improved film clamping assembly does not cause any interference with the wrapping or packaging film being wrapped around the load during the wrapping or packaging operation or cycle.
A further object of the present invention is to provide a new and improved film clamping assembly, and a method of operating the same, for use in connection with film wrapping or packaging machines, wherein the new and improved film clamping assembly does not cause any interference with the wrapping or packaging film being wrapped around the load during the wrapping or packaging operation or cycle so as to enable the wrapping or packaging film to be wrapped around and applied to the lowermost regions of loads, as well as enabling the wrapping of short loads.
A last object of the present invention is to provide a new and improved film clamping assembly, and a method of operating the same, for use in connection with film wrapping or packaging machines, wherein the new and improved film clamping assembly does not cause any interference with the wrapping or packaging film being wrapped around the load during the wrapping or packaging operation or cycle so as to enable a reduced amount of the wrapping or packaging film to be wrapped around and applied to the load and in a relatively shortened operational cycle time.
The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved film clamping assembly, and a method of operating the same, for use in connection with film wrapping or packaging machines, wherein in addition to the clamping members being movable with respect to each other between their OPENED and CLOSED positions, the clamping members can be pivotally moved between a first vertically oriented RAISED position, during which time, for example, the clamping members can capture a portion of the wrapping or packaging film in preparation for the commencement of a wrapping or packaging operation or cycle, and a second horizontally oriented LOWERED position, during which time, for example, the clamping members can retain the captured portion of the packaging or wrapping film while the film wrapping or packaging operation or cycle is being performed. In this manner, the clamping members do not present any interference with respect to the wrapping or packaging film being wrapped around the load, as a result of which, not only can the wrapping or packaging film be applied to the lowermost regions of the load, but in addition, cyclic operation time is shortened and less packaging or wrapping film is required to be used in connection with the wrapping or packaging of a particular load.